Is the mac studio with the Apple M2 Max with 12‑core CPU, 30‑core GPU enough for something like this?
Apple ported Stable Diffusion 1.5/2.1 to MPS themselves.
If they don't so it for SDXL, the port will probably take awhile (if it happens at all).
I've used Apple's port of Stable Diffusion on my Mac Studio with M1 Ultra and it worked flawlessly. I could even download models from Hugging Face and convert them to a CoreML model with little effort using Apple's conversion tool documented in their Stable Diffusion repo [1]. Some models on Hugging Face are already converted – I think anything tagged with CoreML.